The supercell, king of thunderstorms, disruptor of the Great Plains, is a dangerous weather threat wherever it forms. Tornadoes, flooding, enormous hailstones, damaging winds and lightning are some of ...

Thunderstorms need moisture, energy — which meteorologists call instability — and some sort of lift to form. Usually, the lift comes from cold and warmer air masses colliding along a line called a ...

Severe storms eyeing the Chicago area Tuesday have the potential to produce supercells, considered to be one of the most powerful types of storm. But what exactly are they and what makes them so ...